[Hypokalemic periodic paralysis. A case report].

Periodic paralysis is a rare disorder that causes episodes of severe muscle weakness that can be confused with other diseases, including epilepsy or myasthenia gravis. Hyperkalemic and hypokalemic paralysis are included within these diseases, the latter being divided into periodic paralysis (familial, thyrotoxic or sporadic) and non-periodic paralysis. In this regard, we present a case of familial hypokalemic periodic paralysis in an eighteen year-old female who was diagnosed with epilepsy in childhood, as well as a subclinical hypothyroidism (for which she received replacement therapy) months ago. The diagnosis was made by the anamnesis and the confirmation of hypokalemia.